A7.5.2 Descriptions For Lm Parameters - YOKOGAWA digitalYEWFLO Series User Manual

A7.5.2 Descriptions for LM Parameters

The following describes LM parameters of
digitalYEWFLO.
NOTE: Do not turn off the power to the digitalYEWFLO for 60
seconds after making a change to its parameter settings.
(1) DlmeLinkMasterCapabilitiesVariable
Bit
Meaning
Position
LAS Whether the LAS schedule can
Schedule in (= 1) or cannot (= 0) be saved to
B3: 0x04
Non-volatile the non-volatile memory
Memory
Last Values Whether to support (= 1) or not to
B2: 0x02 Record support (= 0) LastValuesRecord.
Supported
Link Master Whether to support (= 1) or not
Statistics to support (= 0)
B1: 0x01
Record DlmeLinkMasterStatisticsRecord.
Supported
(2) DlmeLinkMasterInfoRecord
Sub-
Element
index
1 MaxSchedulingOverhead
2 DefMinTokenDelegTime
3 DefTokenHoldTime
4 TargetTokenRotTime
5 LinkMaintTokHoldTime
6 TimeDistributionPeriod
7 MaximumInactivityToClaimLasDelay
8 LasDatabaseStatusSpduDistributionPeriod
(3) PrimaryLinkMasterFlagVariable
Explicitly declares the LAS. Writing "true" (0xFF)
to this parameter in a device causes that device to
attempt to become the LAS. However, a request
of writing "true" to this parameter in a device is
rejected if the value of the same parameter in any
other device that has a smaller node address within
the same segment is true.
(4) LiveListStatusArrayVariable
A 32-byte variable, in which each bit represents the
status of whether a device on the same segment
is live or not. The leading bit corresponds to the
device address 0x00, and final bit to 0xFF. The
value of LiveListStatusArrayVariable in the case
where devices having the addresses 0x10 and
0x15 in the fieldbus segment is shown below.
<APPENDIX 7. LINK MASTER FUNCTIONS>
Description Value
1
0
0
Size Descrip-
[bytes] tion
1 V(MSO)
2 V(DMDT)
2 V(DTHT)
2 V(TTRT)
2 V(LTHT)
4 V(TDP)
2 V(MICD)
2 V(LDDP)
0x00 00 84 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
Bit correspondences: 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 1 0 0 0 0 1 0 0...
0×10
(5) MaxTokenHoldTimeArray
An 8 × 64-byte variable, in which each set of 2 bytes
represents the delegation time (set as an octet time)
assigned to a device. The delegation time denotes
a time period that is given to a device by means of
a PT message sent from the LAS within each token
circulation cycle.
The leading 2 bytes correspond to the device
address 0x00, and the final 2 bytes to the device
address 0xFF. Specify the subindex to access this
parameter.
(6) BootOperatFunctionalClass
Writing 1 to this parameter in a device and
restarting the device causes the device to start as
a basic device. On the contrary, writing 2 to this
parameter and restarting the device causes the
device to start as an LM.
(7) CurrentLinkSettingRecord and
ConfiguredLinkSettingsRecord
CurrentLinkSettingRecord indicates the
bus parameter settings currently used.
ConfiguredLinkSettingsRecord indicates the
bus parameter settings to be used when the
device becomes the LAS. Thus, when a device
is the LAS, its CurrentLinkSettingRecord and
ConfiguredLinkSettingsRecord have the same
values.
Sub-
Element
index
1 SlotTime
2 PerDlpduPhlOverhead
3 MaxResponseDelay
4 FirstUnpolledNodeId
5 ThisLink
6 MinInterPduDelay
7 NumConsecUnpolledNodeId
8 PreambleExtension
9 PostTransGapExtension
10 MaxInterChanSignalSkew
11 TimeSyncClass
A7-6
0×00
0×15
FA0704.ai
Size Descrip-
[bytes] tion
2 V(ST)
1 V(PhLO)
1 V(MRD)
1 V(FUN)
2 V(TL)
1 V(MID)
1 V(NUN)
1 V(PhPE)
1 V(PhGE)
1 V(PhIS)
1 V(TSC)
IM 01F06F00-01EN